1 /*
2    Copyright (c) 2000, 2015, Oracle and/or its affiliates. All rights reserved.
3 
4    This program is free software; you can redistribute it and/or modify
5    it under the terms of the GNU General Public License, version 2.0,
6    as published by the Free Software Foundation.
7 
8    This program is also distributed with certain software (including
9    but not limited to OpenSSL) that is licensed under separate terms,
10    as designated in a particular file or component or in included license
11    documentation.  The authors of MySQL hereby grant you an additional
12    permission to link the program and your derivative works with the
13    separately licensed software that they have included with MySQL.
14 
15    This program is distributed in the hope that it will be useful,
16    but WITHOUT ANY WARRANTY; without even the implied warranty of
17    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
18    GNU General Public License, version 2.0, for more details.
19 
20    You should have received a copy of the GNU General Public License
21    along with this program; if not, write to the Free Software
22    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301  USA */
23 
24 #ifndef _m_string_h
25 #define _m_string_h
26 
27 #include "my_global.h"                          /* HAVE_* */
28 
29 #include <string.h>
30 
31 #define bfill please_use_memset_rather_than_bfill
32 #define bzero please_use_memset_rather_than_bzero
33 #define bmove please_use_memmove_rather_than_bmove
34 #define strmov please_use_my_stpcpy_or_my_stpmov_rather_than_strmov
35 #define strnmov please_use_my_stpncpy_or_my_stpnmov_rather_than_strnmov
36 
37 #include "mysql/service_my_snprintf.h"
38 
39 #if defined(__cplusplus)
40 extern "C" {
41 #endif
42 
43 /*
44   my_str_malloc(), my_str_realloc() and my_str_free() are assigned to
45   implementations in strings/alloc.c, but can be overridden in
46   the calling program.
47  */
48 extern void *(*my_str_malloc)(size_t);
49 extern void *(*my_str_realloc)(void *, size_t);
50 extern void (*my_str_free)(void *);
51 
52 /* Declared in int2str() */
53 extern char _dig_vec_upper[];
54 extern char _dig_vec_lower[];
55 
56 	/* Prototypes for string functions */
57 
58 extern	void bchange(uchar *dst,size_t old_len,const uchar *src,
59 		     size_t new_len,size_t tot_len);
60 extern	void strappend(char *s,size_t len,pchar fill);
61 extern	char *strend(const char *s);
62 extern  char *strcend(const char *, pchar);
63 extern	char *strfill(char * s,size_t len,pchar fill);
64 extern	char *strmake(char *dst,const char *src,size_t length);
65 
66 extern	char *my_stpmov(char *dst,const char *src);
67 extern	char *my_stpnmov(char *dst, const char *src, size_t n);
68 extern	char *strcont(const char *src, const char *set);
69 extern	char *strxmov(char *dst, const char *src, ...);
70 extern	char *strxnmov(char *dst, size_t len, const char *src, ...);
71 
72 /**
73    Copy a string from src to dst until (and including) terminating null byte.
74 
75    @param dst   Destination
76    @param src   Source
77 
78    @note src and dst cannot overlap.
79          Use my_stpmov() if src and dst overlaps.
80 
81    @note Unsafe, consider using my_stpnpy() instead.
82 
83    @return pointer to terminating null byte.
84 */
my_stpcpy(char * dst,const char * src)85 static inline char *my_stpcpy(char *dst, const char *src)
86 {
87 #if defined(HAVE_BUILTIN_STPCPY)
88   return __builtin_stpcpy(dst, src);
89 #elif defined(HAVE_STPCPY)
90   return stpcpy(dst, src);
91 #else
92   /* Fallback to implementation supporting overlap. */
93   return my_stpmov(dst, src);
94 #endif
95 }
96 
97 /**
98    Copy fixed-size string from src to dst.
99 
100    @param dst   Destination
101    @param src   Source
102    @param n     Maximum number of characters to copy.
103 
104    @note src and dst cannot overlap
105          Use my_stpnmov() if src and dst overlaps.
106 
107    @return pointer to terminating null byte.
108 */
my_stpncpy(char * dst,const char * src,size_t n)109 static inline char *my_stpncpy(char *dst, const char *src, size_t n)
110 {
111 #if defined(HAVE_STPNCPY)
112   return stpncpy(dst, src, n);
113 #else
114   /* Fallback to implementation supporting overlap. */
115   return my_stpnmov(dst, src, n);
116 #endif
117 }
118 
my_strtoll(const char * nptr,char ** endptr,int base)119 static inline longlong my_strtoll(const char *nptr, char **endptr, int base)
120 {
121 #if defined _WIN32
122   return _strtoi64(nptr, endptr, base);
123 #else
124   return strtoll(nptr, endptr, base);
125 #endif
126 }
127 
my_strtoull(const char * nptr,char ** endptr,int base)128 static inline ulonglong my_strtoull(const char *nptr, char **endptr, int base)
129 {
130 #if defined _WIN32
131   return _strtoui64(nptr, endptr, base);
132 #else
133   return strtoull(nptr, endptr, base);
134 #endif
135 }
136 
my_strtok_r(char * str,const char * delim,char ** saveptr)137 static inline char *my_strtok_r(char *str, const char *delim, char **saveptr)
138 {
139 #if defined _WIN32
140   return strtok_s(str, delim, saveptr);
141 #else
142   return strtok_r(str, delim, saveptr);
143 #endif
144 }
145 
146 /* native_ rather than my_ since my_strcasecmp already exists */
native_strcasecmp(const char * s1,const char * s2)147 static inline int native_strcasecmp(const char *s1, const char *s2)
148 {
149 #if defined _WIN32
150   return _stricmp(s1, s2);
151 #else
152   return strcasecmp(s1, s2);
153 #endif
154 }
155 
156 /* native_ rather than my_ for consistency with native_strcasecmp */
native_strncasecmp(const char * s1,const char * s2,size_t n)157 static inline int native_strncasecmp(const char *s1, const char *s2, size_t n)
158 {
159 #if defined _WIN32
160   return _strnicmp(s1, s2, n);
161 #else
162   return strncasecmp(s1, s2, n);
163 #endif
164 }
165 
166 /* Prototypes of normal stringfunctions (with may ours) */
167 #ifndef HAVE_STRNLEN
168 extern size_t strnlen(const char *s, size_t n);
169 #endif
170 
171 extern int is_prefix(const char *, const char *);
172 
173 /* Conversion routines */
174 typedef enum {
175   MY_GCVT_ARG_FLOAT,
176   MY_GCVT_ARG_DOUBLE
177 } my_gcvt_arg_type;
178 
179 double my_strtod(const char *str, char **end, int *error);
180 double my_atof(const char *nptr);
181 size_t my_fcvt(double x, int precision, char *to, my_bool *error);
182 size_t my_gcvt(double x, my_gcvt_arg_type type, int width, char *to,
183                my_bool *error);
184 
185 #define NOT_FIXED_DEC 31
186 
187 /*
188   The longest string my_fcvt can return is 311 + "precision" bytes.
189   Here we assume that we never cal my_fcvt() with precision >= NOT_FIXED_DEC
190   (+ 1 byte for the terminating '\0').
191 */
192 #define FLOATING_POINT_BUFFER (311 + NOT_FIXED_DEC)
193 
194 /*
195   We want to use the 'e' format in some cases even if we have enough space
196   for the 'f' one just to mimic sprintf("%.15g") behavior for large integers,
197   and to improve it for numbers < 10^(-4).
198   That is, for |x| < 1 we require |x| >= 10^(-15), and for |x| > 1 we require
199   it to be integer and be <= 10^DBL_DIG for the 'f' format to be used.
200   We don't lose precision, but make cases like "1e200" or "0.00001" look nicer.
201 */
202 #define MAX_DECPT_FOR_F_FORMAT DBL_DIG
203 
204 /*
205   The maximum possible field width for my_gcvt() conversion.
206   (DBL_DIG + 2) significant digits + sign + "." + ("e-NNN" or
207   MAX_DECPT_FOR_F_FORMAT zeros for cases when |x|<1 and the 'f' format is used).
208 */
209 #define MY_GCVT_MAX_FIELD_WIDTH (DBL_DIG + 4 + MY_MAX(5, MAX_DECPT_FOR_F_FORMAT)) \
210 
211 extern char *llstr(longlong value,char *buff);
212 extern char *ullstr(longlong value,char *buff);
213 
214 extern char *int2str(long val, char *dst, int radix, int upcase);
215 extern char *int10_to_str(long val,char *dst,int radix);
216 extern char *str2int(const char *src,int radix,long lower,long upper,
217 			 long *val);
218 longlong my_strtoll10(const char *nptr, char **endptr, int *error);
219 #if SIZEOF_LONG == SIZEOF_LONG_LONG
220 #define ll2str(A,B,C,D) int2str((A),(B),(C),(D))
221 #define longlong10_to_str(A,B,C) int10_to_str((A),(B),(C))
222 #undef strtoll
223 #define strtoll(A,B,C) strtol((A),(B),(C))
224 #define strtoull(A,B,C) strtoul((A),(B),(C))
225 #else
226 extern char *ll2str(longlong val,char *dst,int radix, int upcase);
227 extern char *longlong10_to_str(longlong val,char *dst,int radix);
228 #endif
229 #define longlong2str(A,B,C) ll2str((A),(B),(C),1)
230 
231 #if defined(__cplusplus)
232 }
233 #endif
234 
235 /*
236   LEX_STRING -- a pair of a C-string and its length.
237   (it's part of the plugin API as a MYSQL_LEX_STRING)
238   Ditto LEX_CSTRING/MYSQL_LEX_CSTRING.
239 */
240 
241 #include <mysql/mysql_lex_string.h>
242 typedef struct st_mysql_lex_string LEX_STRING;
243 typedef struct st_mysql_const_lex_string LEX_CSTRING;
244 
245 #define STRING_WITH_LEN(X) (X), ((sizeof(X) - 1))
246 #define USTRING_WITH_LEN(X) ((uchar*) X), ((sizeof(X) - 1))
247 #define C_STRING_WITH_LEN(X) ((char *) (X)), ((sizeof(X) - 1))
248 
249 
250 /**
251   Skip trailing space.
252 
253   On most systems reading memory in larger chunks (ideally equal to the size of
254   the chinks that the machine physically reads from memory) causes fewer memory
255   access loops and hence increased performance.
256   This is why the 'int' type is used : it's closest to that (according to how
257   it's defined in C).
258   So when we determine the amount of whitespace at the end of a string we do
259   the following :
260     1. We divide the string into 3 zones :
261       a) from the start of the string (__start) to the first multiple
262         of sizeof(int)  (__start_words)
263       b) from the end of the string (__end) to the last multiple of sizeof(int)
264         (__end_words)
265       c) a zone that is aligned to sizeof(int) and can be safely accessed
266         through an int *
267     2. We start comparing backwards from (c) char-by-char. If all we find is
268        space then we continue
269     3. If there are elements in zone (b) we compare them as unsigned ints to a
270        int mask (SPACE_INT) consisting of all spaces
271     4. Finally we compare the remaining part (a) of the string char by char.
272        This covers for the last non-space unsigned int from 3. (if any)
273 
274    This algorithm works well for relatively larger strings, but it will slow
275    the things down for smaller strings (because of the additional calculations
276    and checks compared to the naive method). Thus the barrier of length 20
277    is added.
278 
279    @param     ptr   pointer to the input string
280    @param     len   the length of the string
281    @return          the last non-space character
282 */
283 #if defined(__sparc) || defined(__sparcv9)
skip_trailing_space(const uchar * ptr,size_t len)284 static inline const uchar *skip_trailing_space(const uchar *ptr,size_t len)
285 {
286   /* SPACE_INT is a word that contains only spaces */
287 #if SIZEOF_INT == 4
288   const unsigned SPACE_INT= 0x20202020U;
289 #elif SIZEOF_INT == 8
290   const unsigned SPACE_INT= 0x2020202020202020ULL;
291 #else
292 #error define the appropriate constant for a word full of spaces
293 #endif
294 
295   const uchar *end= ptr + len;
296 
297   if (len > 20)
298   {
299     const uchar *end_words= (const uchar *)(intptr)
300       (((ulonglong)(intptr)end) / SIZEOF_INT * SIZEOF_INT);
301     const uchar *start_words= (const uchar *)(intptr)
302        ((((ulonglong)(intptr)ptr) + SIZEOF_INT - 1) / SIZEOF_INT * SIZEOF_INT);
303 
304     DBUG_ASSERT(end_words > ptr);
305     while (end > end_words && end[-1] == 0x20)
306       end--;
307     if (end[-1] == 0x20 && start_words < end_words)
308       while (end > start_words && ((unsigned *)end)[-1] == SPACE_INT)
309         end -= SIZEOF_INT;
310   }
311   while (end > ptr && end[-1] == 0x20)
312     end--;
313   return (end);
314 }
315 #else
316 /*
317   Reads 8 bytes at a time, ignoring alignment.
318   We use uint8korr, which is fast (it simply reads a *ulonglong)
319   on all platforms, except sparc.
320 */
skip_trailing_space(const uchar * ptr,size_t len)321 static inline const uchar *skip_trailing_space(const uchar *ptr, size_t len)
322 {
323   const uchar *end= ptr + len;
324   while (end - ptr >= 8)
325   {
326     if (uint8korr(end-8) != 0x2020202020202020ULL)
327       break;
328     end-= 8;
329   }
330   while (end > ptr && end[-1] == 0x20)
331     end--;
332   return (end);
333 }
334 #endif
335 
lex_string_set(LEX_STRING * lex_str,const char * c_str)336 static inline void lex_string_set(LEX_STRING *lex_str, const char *c_str)
337 {
338   lex_str->str= (char *) c_str;
339   lex_str->length= strlen(c_str);
340 }
341 
lex_cstring_set(LEX_CSTRING * lex_str,const char * c_str)342 static inline void lex_cstring_set(LEX_CSTRING *lex_str, const char *c_str)
343 {
344   lex_str->str= c_str;
345   lex_str->length= strlen(c_str);
346 }
347 
348 #endif
349